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Invasive species have historically disrupted environments by outcompeting, displacing, and extirpating native species, resulting in significant environmental and economic damage. Developing approaches to detect the presence of invasive species, favorable habitats for their establishment, and predicting their potential spread are underutilized management strategies to effectively protect the environment and the economy. Spotted lanternfly (SLF, Lycorma delicatula) is a phloem-feeding planthopper native to China that poses a severe threat to horticultural and forest products in the United States. Tools are being developed to contain the spread and damage caused by SLF; however, methods to rapidly detect novel infestations or low-density populations are lacking. Vegetation spectroscopy is an approach that can represent vegetation health through changes in the reflectance and absorption of radiation based on plant physiochemical status. Here, we hypothesize that SLF infestations change the spectral and chemical characteristics of tree canopies. To test this hypothesis, we used a full range spectroradiometer to sample canopy foliage of silver maple (Acer saccharinum) and red maple (Acer rubrum) trees in a common garden in Berks County, Pennsylvania that were exposed to varying levels of SLF infestation. Foliar spectral profiles separated between SLF infestation levels, and the magnitude of separation was greater for the zero-SLF control compared with higher infestation levels. We found the red-edge and portions of the NIR and SWIR regions were most strongly related to SLF infestation densities and that corresponding changes in vegetation indexes related to levels of chlorophyll were influenced by SLF infestations, although we found no change in foliar levels of chlorophyll. We found no influence of SLF densities on levels of primary metabolites (i.e., pigments, nonstructural carbohydrates, carbon, and nitrogen), but did find an increase in the phenolic compound ferulic acid in response to increasing SLF infestations; this response was only in red maple, suggesting a possible species-specific response related to SLF feeding. By identifying changes in spectral and chemical properties of canopy leaves in response to SLF infestation, we can link them together to potentially better understand how trees respond to SLF feeding pressure and more rapidly identify SLF infestations. [ABSTRACT FROM AUTHOR]

Insecticidal pathogens such as baculoviruses are currently under intensive development as biorational agents for the control of lepidopteran pests. However, because the efficacy of these orally infective viruses is influenced by host diet, our ability to use baculoviruses effectively in an integrated pest management program requires understanding the influence of dietary components on the disease process. Nutritional stress caused by differences in the quality (casein or soy) or quantity (0-8%) of dietary protein altered the postinfectional course of disease caused by Autogropha californica M nucelopolyhedrovirus in 2 species of noctuids, Heliothis virescens (F.) and Tnchoplusia ni (Hubner). Lethal times of larvae infected with either the wild-type virus or a recombinant expressing a scorpion toxin (AaIT) derived from this parent virus were similarly affected by dietary protein. In general, the higher the level of dietary protein the shorter the lethal times. However, the influence of protein quality on lethal times depended on the insect species tested. The effect of chlorogenic acid on disease depended on dietary protein levels. At high protein concentrations, chlorogenic acid decreased speed of kill; whereas, at low protein levels, the phenolic had the opposite effect. The common factor among all treatments was that the faster larvae grew, the faster they died from viral infection. We suggest that insects that grow faster may support faster rates of viral replication in infected hosts. From an ecological perspective, it is possible that plants of higher protein content may increase the potential for the development of baculoviral epizootics in insect populations.

Baculoviruses are arthropod-specific, dsDNA viruses primarily used to control lepidopteran pests. A limitation of the use of baculoviruses for pest control is that their efficacy is modifiable by host-plant chemicals. The levels of phenolic substrates and two foliar oxidative enzymes, peroxidase(POD) and polyphenol oxidase (PTO), were significant predictors of disease caused by a baculovirus in Heliothis virescens fed on either cotton or lettuce; POD was the more influential of the two enzymes. The higher the plant phenolase activity, the lower the percent mortality and the slower the insects died from viral infection. Whether a particular class of phenolic substrates was correlated with enhanced or attenuated baculoviral disease depended upon context, i.e.. admixture. Diminution of viral efficacy by plant oxidative activity may compromise the compatibility of baculoviruses with other components of an integrated pest management system such as host plant resistance.

Spotted lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae), is an invasive insect that was first detected in the United States in 2014 and feeds on a wide variety of plants, with economic impacts on the agricultural, ornamental, and timber industries. Part of what likely contributes to the success of L. delicatula in its invaded range is that it appears to be chemically defended by sequestering toxins from its host plant(s), which may deter predators in the introduced range. To determine the identity and behavior of North American predators that feed on spotted lanternfly, we performed a community science study in which we asked members of the public to contribute reports of animals feeding on spotted lanternfly through a Facebook page. The largest group of reported predators was arthropods followed by birds. Araneae was the arthropod order with the most reports and Phasianidae was the most frequently reported bird family. Using Pearson's χ 2 tests, we also identified significant relationships between predator behavior and (1) taxonomic group of the predator, (2) L. delicatula life stage, and (3) host plant L. delicatula was observed on. These results can help to guide future research on predator host shifting to spotted lanternfly and potential for biocontrol as a management tactic. [ABSTRACT FROM AUTHOR]

For the invasive planthopper Lycorma delicatula , eggs are an attractive target for surveys and management because they can persist from September through May before hatching, and remnants may be retained for years after hatching. Efforts to control this invasive species, though, are hampered by imperfect detection, which impedes early detection and rapid response, obscures management impacts, and reduces the fraction of egg masses that can be managed. To estimate egg mass detectability, we conducted 75 duplicate surveys of 20 × 5 m plots located in forest edges and disturbed areas frequently used by L. delicatula. We fit binomial mixture models and investigated the effects of weather, height (above or below 3 m), season (winter or spring), and basal area of trees within plots, finding no evidence that these factors affected detection rate, which averaged 52.2%. We additionally estimated the fraction of L. delicatula eggs that were laid above 3 m, putting them outside of easy reach for management by scraping or targeted ovicide application. This proportion varied with basal area of trees within plots, and the estimated mean was greater than 50% across the range of basal areas in study plots. Finally, we found that counts of old egg masses correlated with counts of new egg masses laid the year prior, but the ability to infer prior years' egg mass counts was limited. Together, these findings inform managers delimiting L. delicatula populations in mixed habitats and those treating egg masses to slow population growth and spread of this pest. [ABSTRACT FROM AUTHOR]